Biochemical Pathways and Energy Production in Cells

This set of flashcards covers key vocabulary related to cellular respiration, glycolysis, the citric acid cycle, and ATP synthesis.

Glycolysis

The process by which glucose is broken down in the cytosol to produce energy in the form of ATP.

Cytosol

The fluid part of the cytoplasm where glycolysis occurs.

Anaerobic Respiration

A form of respiration that occurs without oxygen; includes glycolysis followed by fermentation.

Fermentation

The metabolic process that regenerates NAD+ from NADH to allow glycolysis to continue in the absence of oxygen.

Mitochondria

Organelles in eukaryotic cells where aerobic respiration occurs.

Citric Acid Cycle (Krebs Cycle)

A series of chemical reactions used by all aerobic organisms to generate energy through oxidation of acetyl-CoA.

NADH

A reduced form of NAD+ that carries electrons to the electron transport chain.

Electron Transport Chain

A series of protein complexes in the mitochondrial membrane that transfer electrons from NADH and FADH2 to oxygen, building a proton gradient.

ATP Synthase

An enzyme that uses the energy from a proton gradient to synthesize ATP from ADP and inorganic phosphate.

Oxidative Phosphorylation

The metabolic pathway in which ATP is produced as electrons are transferred to oxygen via the electron transport chain.

Hydrogen Ion Gradient

The difference in concentration of hydrogen ions across the mitochondrial membrane, which drives ATP synthesis.

Oxygen as Final Electron Acceptor

Oxygen's role in the electron transport chain, vital for accepting electrons and forming water.

Uncouplers

Substances that allow hydrogen ions to bypass ATP synthase, reducing ATP production while increasing oxygen consumption.

Prokaryotes vs. Eukaryotes

Prokaryotes lack a mitochondria and perform respiration differently compared to eukaryotes, which use mitochondria.

Substrate Level Phosphorylation

A method of producing ATP where a phosphate group is directly transferred to ADP from a phosphorylated intermediate.

Acetyl-CoA

The molecule that enters the citric acid cycle, produced from the breakdown of glucose and fatty acids.

FADH2

A molecule similar to NADH that also carries electrons to the electron transport chain, generated during the citric acid cycle.

Cytoplasm

The part of the cell where glycolysis and other metabolic pathways take place.